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多年来,安徽沿江各地农技人员和广大棉农在棉花高产栽培技术方面不断探索、实践和创新,其高产栽培技术业已应用多年,且逐渐成熟,现总结归纳如下,供大家参考和探讨。1磷肥改集中施用为分散撒施磷肥集中施用的传统理论依据是磷肥在土壤中移动性差。实际上恰恰是因为磷肥有此特性,更应全面撒施,使其分布于整个土壤耕作层。由于作物根系是布满整个耕作层的,撒施在土壤中的磷肥与集中点施在土壤中的且因磷肥相比,扩大了与作物根系的接触面,更有利于作物吸收。一般在翻耕土壤时撒施,肥料利用率比打穴点施要提高30%以上,没有条件撒施的,开沟条施也… 相似文献
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为研究维生素C对原代培养建鲤肠道上皮细胞(IECs)增殖分化、结构和功能的影响,原代培养建鲤肠道上皮细胞72h,换用含维生素C浓度分别为0、4、10、16、22、28mg/L的DMEM培养液,继续培养72h后,观察细胞培养特性和测定细胞蛋白含量、钠钾ATP酶(Na+、K+-ATP酶)、谷草转氨酶(GOT)和谷丙转氨酶(GPT)活性。结果显示,未添加维生素C的建鲤IECs存活数量少,细胞集落较小;添加不同浓度维生素C的试验组建鲤,其细胞贴壁数量明显增多,细胞集落较大并有成片单层细胞,不同试验浓度组间差异不显著;添加不同浓度维生素C的试验组建鲤IECs,MTT OD值、碱性磷酸酶(AKP)、谷丙转氨酶、谷草转氨酶,Na+、K+-ATP酶活性和IECs蛋白含量均显著提高(P<0.05),且培养液中乳酸脱氢酶(LDH)活性显著降低(P<0.05);10mg/L维生素C浓度试验组建鲤IECs的碱性磷酸酶、谷草转氨酶、谷丙转氨酶的活性可增加到最大值,16mg/L维生素C浓度试验组建鲤IECs的Na+、K+-ATP酶活性和蛋白含量增加到最大值。提示适当添加维生素C可以促进建鲤肠道上皮细胞增殖分化,改善细胞膜结构的完整性,增强肠上皮细胞的功能和氨基酸代谢,提高细胞蛋白质沉积。 相似文献
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This study was conducted to examine the responses of earthworms to soil organic matter and litter at different decomposition stages and their contributions in litter decomposition processes in southern subtropical areas of China. Two plantations were selected as the study sites: Site Ⅰ was dominated by the exotic endogeic earthworm species Ocnerodrilus occidentalis; Site Ⅱ was dominated by epigeic species Amynthas corticis. After the fallen litter and earthworms were removed or expelled, four treatments were set up as: reserving the top soil (0-5 cm, equal to H layer) (H), removing the top soil and adding fresh litter (Le), removing the top soil and adding semi-decomposed litter (Li), and a control with no top soil nor any litter (CK). Five randomized blocks that were enclosed with nylon nets on the top were set up in each site, and then the four treatments were arranged randomly in each block. After 2-3 months, earthworms were collected using the formalin method. The results showed that Ocnerodrilus occidentalis preferred Treatment H though it was found in Treatments Le and Li as well; Amynthas corticis preferred Treatment Li though sometimes it also appeared in Treatment H; and Amynthas sp., another epigeic species, was mainly present under Treatment Le and only appeared in Treatment H occasionally. These findings confirmed that earthworm species belonging to different ecological groups had different responses to organic matter at different decomposition stages. The impacts of earthworm communities dominated by O.occidentalis mainly appeared at the later periods of litter decomposition. 相似文献
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携带溶菌酶基因的高回交转育后代抗瘟性研究 总被引：1，自引：0，他引：1
进一步明确溶菌酶基因回交转育利用对于强优恢复系“明恢63”稻瘟病抗性改良的效果, 运用苗期人工接种和大田穗颈瘟鉴定相结合的方法, 研究了携带溶菌酶基因的高回交转育纯系对于稻瘟病的抗谱特性和穗颈瘟抗性。结果表明: 回交纯系对所应试的76个菌株中的6~8个感病, 稻瘟抗性频率为90%左右, 属高抗水平; 而轮回亲本“明恢63”对21个菌株感病, 抗性频率为72.37%, 属中抗水平。穗颈瘟调查分析表明, 回交转育纯系比轮回亲本发病率平均降低10%左右, 发病指数平均降低15%左右, 经T值检验二者在穗颈瘟抗性水平上差异达极显著水平, 回交转育纯系抗性评价为抗性(R)级, 轮回亲本为中感(MS)级。因此溶菌酶基 因的转育利用确能有效拓宽抗谱, 提高稻瘟病抗性水平, 这些回交转育品系在抗病育种上具有较高的应用 潜力。 相似文献
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Hesperidin is a flavanone glycoside widely available for dietary intake in citrus fruits or citrus fruit derived products; however, exhaustive and reliable data are scarcely available for biological activity when it exerts protective health effects in humans. The principal intent of this work is to check binding domain and structural changes of human serum albumin (HSA), the primary carrier of flavonoids, in blood plasma association with hesperidin by employing molecular modeling, steady state and time-resolved fluorescence, and circular dichroism (CD) methods. From molecular modeling simulations, subdomains IIA and IIIA, which correspond to Sudlow's sites I and II, respectively, were earmarked to possess affinity for hesperidin, but the affinity of site I with flavanone is greater than that of site II. This corroborates the site-specific probe and hydrophobic 8-anilino-1-naphthalenesulfonic acid (ANS) displacement results placing the hesperidin at warfarin-azapropazone and indole-benzodiazepine sites. Steady state and time-resolved fluorescence manifested that static type, due to HSA-hesperidin complex formation (1.941 × 10(4) M(-1)), is the operative mechanism for the diminution in the tryptophan (Trp)-214 fluorescence. Moreover, via alterations in three-dimensional fluorescence and CD spectral properties, we can securely draw the conclusion that the polypeptide chain of HSA is partially destabilized after conjugation with hesperidin. We anticipate that this study can provide better knowledge of bioavailability such as absorption, biodistribution, and elimination, of hesperidin in vivo, to facilitate the comprehension of the biological responses to physiologically relevant flavanones. 相似文献
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无土栽培中应用有机肥料的研究进展 总被引：3，自引：0，他引：3
本文介绍了无土栽培中有机肥和有机基质的种类和作用。无土栽培中有机肥来源广泛,其丰富的营养成分促进作物的生长发育,提高作物的产量和品质。有机基质的作用也表现在对作物的生长发育、产量及品质方面的影响。本文还对无土栽培中应用有机肥料的研究课题进行了讨论。 相似文献
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《机械制造基础》课程教学方法探讨 总被引：5，自引：1，他引：4
指出了在新技术条件下《机械制造基础》的教学必须改革，以适应我国高等教育的发展和国民经济建设的需要，并具体阐述了改革后《机械制造基础》课程的教学方法。 相似文献
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